800 CYRUS BALLOU COMSTOCK. 



determine not only the topography and hydrography of the region, 

 but also to be of geodetic value. The measurements were made Avith 

 extreme accuracy, involving eight primary base lines, a primary tri- 

 angulation about 1650 miles in length, and a hydrographic survey 

 covering nearly 10,000 square miles, and also the investigation of the 

 earth's magnetism. His report on this great work, published as 

 Professional Paper No. 24 of the Corps of Engineers, in 1882, is a docu- 

 ment of great value and permanent interest to geodesists, and is a 

 monument to his professional ability and that of his associates. 



General Comstock was also engaged in studies relating to the 

 improvement of rivers and deltas, and was sent to Europe to investi- 

 gate these subjects. He served on several boards, and was Super- 

 intending Engineer to examine the progress of jetties built by Captain 

 Eads at the mouth of the Mississippi. He was a member of the 

 Mississippi River commission for 16 years, and its President for 

 five years, during which time he had to deal with many difficult 

 hydraulic problems. He was also a member of the permanent Board 

 of Engineers for fortifications and riA-er and harbor improvements, 

 and commanded the Engineer School of Application at Willets Point, 

 New York, for about a year. 



General Comstock was a member of the National Academy of 

 Sciences, to which he donated a trust fund to be devoted to researches 

 in electricity, magnetism and radiant energy, the value of which 

 subjects his own experience had led him to appreciate. He became a 

 member of the American Academy of Arts and Sciences in 1892. 



In addition to his classic report on the Lake survey, General Com- 

 stock's name appears as a signer of the reports of sixty local engineer- 

 ing boards, of twenty-one of which he was President. His life 

 furnished a good illustration of the value of science to the professional 

 engineer, and of the value of the engineer to science. -"^ He died at 

 New York City, May 29, 1910. 



G. F. Swain. 



1 This memoir is abstracted from a longer memoir of General Comstock by 

 General Henry L. Abbot, in the annual of the association of graduates of the 

 United States Military Academy, in 1912. 



